1. Field of the Invention
The present invention concerns a method for operation of a medical imaging apparatus, of the type wherein an examination subject (in particular a patient) is located on a recumbent board.
2. Description of the Prior Art
An imaging diagnostic device with a recumbent board is, for example, known from DE 199 20 008 A1.
In medical imaging methods, for example computed tomography, a patient located on a recumbent board is frequently displaced relative to a scan region of a diagnostic apparatus during the examination. In many cases, the recumbent board is supported only at one end, such that it inevitably bends with increasing forward displacement of the recumbent board. The deflection cannot be completely avoided even with a recumbent board that is designed to minimize instability. A minimization of the deflection of the recumbent board can in fact be achieved by providing the board with a multi-sided support, but this requires an elaborate track design for the movement mechanism.
As long as only a single data (image) acquisition is undertaken in a specific cross-section plane of the tissue to be examined, a slight deflection of the recumbent board is not of concern in some cases. By contrast, exact knowledge of the position (in particular also the height position) of the recumbent board is of great importance when either various exposures of the same tissue region must be superimposed, and/or when three-dimensional data are to be generated from exposures in various cross-section planes. The latter applies both in the case of separate exposures in various cross-section planes and in cases in which a continuous feed ensues during the imaging diagnosis, for example in spiral computed tomography. Radiation therapy is a field of application in which an exact association of medical imaging data with the position of the examined tissue in the examination subject is of particular importance.